NEW YORK — Today's teens are constantly on their smartphones, many check social media "constantly" and prefer texting over face-to-face communication.

But a new poll finds that these same teens also say that social media has a positive effect on their lives, helping them feel more confident, less lonely and less depressed.

The poll was released Monday by Common Sense Media, a San Francisco-based nonprofit group focused on kids' use of media and technology. It found that 89 percent of teenagers have their own smartphone. That's up from 41 percent in 2012, the last time the survey was conducted.

But while 2012's teens were all over Facebook, the age group's presence on the social network has plummeted in the past six years. Only 15 percent of teens now say Facebook is their main social network. In 2012, 68 percent did.

Today, 44 percent of teens say their primary social network is Snapchat, making it the most popular social media app, followed by Instagram (which is owned by Facebook) at 22 percent.

Among the survey's other findings:

— The majority of teens — 59 percent — said social media makes no difference in how depressed they feel. Twenty-nine percent, meanwhile, said it makes them feel less depressed and 11 percent said it makes them more depressed. Thirty-nine percent said it makes them feel less lonely and 13 percent, more lonely.

— Thirty-five percent of teens said texting is their favorite way to communicate with friends, compared with 33 percent in 2012. Only 32 percent said talking in person is their preferred method of communication, down from 49 percent among 2012 teens.

— Almost three-quarters of teens said they believe that tech companies manipulate people into spending more time on their devices and more than half said using social media often distracts them from homework.

— Sixty-four percent of teen social-media users said they come across racist, sexist or homophobic or other hateful content either sometimes or often.

— Sixteen percent of teens use social media "almost constantly," while 19 percent never do.

— Thirteen percent of teenagers said they have been cyberbullied. Nearly a quarter, meanwhile, has tried to help a person who has been cyberbullied by talking to them or reporting it to an adult.

— More than half said parents worry too much about social media — on the other hand, 46 percent think parents would be a lot more worried if they knew what "actually happens" online.

The survey was conducted in March and April among 1,141 13- to 17-year-olds nationwide. The margin of error is 3.4 percentage points.